Sonic process for materials separation



1963 A. G. BODINE,IJR 3,076,545

some PROCESS FOR MATERIALS SEPARATION Filed Oct. 5, 1960 United States Patent M 3,076,545 SONIC PROCESS FOR MATERIALS SEPARATION Albert G. Bodine, Jr., Sherman Oaks, Calif. (3300 Cahuenga Blvd., Los Angeles 28, Calif.) Filed Oct. 5, 1960, Ser. No. 60,686 3 Claims. (Cl. 2091) This invention is concerned with a process for partial separation of minerals from earthen material in dry state. It is particularly useful for low grade ores. I have found that with my process I can produce commercial grade ores, such as 0.218% uranium from very low grade ore such as 0.07% uranium. This can be accomplished, I have found, with a sound wave action.

In my process I generate an elasticsound wave in a plate member. This sound wave is established at a frequency which causes the plate to resonate with a characteristic pattern having uniformly graduated value of acceleration. A body of the raw ore, comprising a fluent mixture of solid'granular materials of diifering density and/or particle size, is placed upon this plate in contiguous direct vibration transmission contact therewith and with the particles of this body of material in contiguous contact with each other. The sound wave pattern on the plate causes the dry ore to become vibrant and fluid. The body of ore attains a dynamically sustained state, and literally flows across the plate like water.

As the ore flows across the plate it is subjected to grad ually increasing and decreasing acceleration values as it passes various regions of the plate. These accelerations cause the more valuable mineral to be thrown up in the air above the plate and above the body of the ore which is in contiguous contact with the plate. The ore, such as uranium, is thrown higher than is the sand and other earthen material.

The next step is to remove the so separated ore. This I sometimes accomplish by blowing a current of air over the body of material on the plate. Then, by passing this air through a dust collector, the high grade ore can be removed for storage or other disposition.

My invention can be understood by observing the process as applied to the apparatus shown in the accompanying drawings. In these drawings, FIG. 1 is a side elevation, partly in section, of a typical apparatus in simple form for practicing this method of the invention; and FIG. 2 is an end view, partly in section, of the apparatus of FIG. 1.

Referring to FIG. 1, a preferably sloping plate is made to vibrate with the acoustic standing wave pattern 11 as shown, so that the two ends vibrate up and down in unison while the center vibrates always in the opposite direction. The vibration, it will be observed, is always normal to the plate. This I accomplish by creating a resonant elastic vibration of the plate 10. The plate flexes elastically, with a pattern such as indicated at 11. Velocity nodes appear at V, and velocity antinodes at V It is possible to operate plate 10 at overtones, so that there will appear more regions of such elastic vibration (more nodes and antinodes).

There are a number of wave generators or vibratory driver means which are capable of creating the above described vibration pattern in plate 10. In FIGS. 1 and 2 are shown one suitable form of such vibratory driver. Motor 12 transmits rotary power through flexible drive shaft 13 to unbalanced rotary shaft 14 which is carried by bearing members 15 as shown. Vibratory impulses from the rotation of shaft 14, with unbalanced masses 16, are applied through bearing means 15 to plate 10 upon which bearing means 15 are mounted. The vibratory driver is seen to be connected to a velocity antinode of the plate. The power output of the driver is established high enough to elevate the acceleration factor Patented Feb. 5, 1963 of the plate to a range in which the body of ore becomes dynamically sustained and fluent as described above. V i I Plate 10 is supported by flexible mounts 20 which are carried by sloping base structure 21 as shown. Housing, 22, which is mounted on base 21, supports feed vessel 23. Mounted in vessel 26 is rotating impeller 25 which is belt driven, through suitable pulleys, by motor 30 also mounted on vessel 23. Vessel 23 directs input ore onto impeller 25 which in turn breaks up the ore by impact action of impeller blades 26. The ore is then conducted through conduit portion 32 of vessel 23 onto the'elevated end of plate 10.

Reject material from the lower edge of plate 10 is carried away by conveyer belt 40. Airborne material, which is tossed up by vibrating plate 10, and thus separated from the main body of material on the plate, enters the air current created by suction blower 45, driven by an electric motor, not shown, in the conventional manner. The output from blower 45 discharges into dust collector 50 where the solid material is stopped by filter screen 52. Such solid material then drops to the bottom of collector 50, from whence it can be periodically dumped by opening valve 55. This is the de sired material. A v

The method of this invention, as practiced with the apparatus described above, is carried out as follows: Crushed ore is delivered to vessel 23, where it'is subjected to further pulverizing by impact of impeller blades 26. This input ore then falls onto plate 10. It will be noted that plate 10 is inclined, so that the ore slides down the surface of plate 10 as it is maintained in a loose and fluid state by the vibrations of plate 10.

Plate 10 is made to vibrate elastically in an acoustic standing wave pattern, as exemplified at 11, by virtue of sound waves imparted to plate 10 as shaft 14 rotates. Therefore the ore is subjected to gradually changing amounts of acceleration as it progresses through the acoustic pattern. As the ore slides down the inclined plate 10 as shown it experiences gradually decreasing acceleration, then gradually increasing acceleration as it approaches the center region of the plate, than gradually decreasing acceleration and finally an increasing acceloration as it leaves the lower edge of the plate. This changing field of acceleration causes the valuable constituents to migrate to characteristic regions in the ore body on the plate, from whence it can be removed by suitable means.

In the example of uranium ores, the more valuable material tends to accumulate together and then be thrown up into the air space above the plate. In this instance the method employs a current of air passing through this air space in housing 23, flowing from input vessel passage 32 to suction blower 45 above the body or layer of material remaining on the plate. This airborne material can then be collected by any suitable means such as dust collector 50 described above.

The reason for the agglomerating tendency of like-kind particles under the described conditions of the invention, and the tendency for these agglomerating particles to migrate together to characteristic regions of the sound wave pattern in the plate, i.e., to be diiferentially motivated to travel certain paths to certain stations in the main body of the ore, has been extensively studied, but remains obscure. It is clear that the process is a drystate one, requiring essential looseness, freedom and mobility of individual particles. Also, the described differential motivation, migration, agglomerization, and upward tossing of the recovered component of the ore occurs when the body of ore is subjected exclusively to the differential motivating influences of the sound wave action in the plate on which is resides, undisturbed by fluid carrier fiow through the ore body.

The differential migration and agglomeration effect has been variously attributed by scientists who have observed the process to non-linear motivating effects characteristic of a form of dry-state cavitation, to differential impact effects of particles of different coefficients of elasticity, to differential amounts of kinetic energy received by particles of the different materials, and to an application of the principle of least work. Whatever the true explanation may be, the phenomenon which I have discovered is striking, unique and highly useful in the collection and separation of desired components of certain ore bodies, such as uranium salts from ore.

This application is a continuation-in-part of my prior application entitled Sonic Materials Separation Process and Apparatus, filed September 29, 1959, Serial No. 843,269, now abandoned, and also of my parent application of the same title, filed March 19, 1956, Serial No. 572,432, now abandoned.

Having now described my invention, I claim as follows;

1. The method of separating a desired constituent solid granular material from a mixture of solid granular materials of differing density and/or particle size in a dry state, that comprises: placing a fluent body of dry particles of said mixture of materials in contiguous contact with each other andin direct vibration transmission contact with a vibrating Wave radiating surface vibrated by a sound wave generator, vibrating said surface with a vibration pattern having a component of vibration normal to the area of contact between said surface and said body, establishing the output power of said sound Wave generator so as to maintain the acceleration factor of said vibration of said surface in the range wherein particles of said body can be observed dynamically sustained in a flowing condition like a liquid, maintaining said body of materials in said dynamically sustained condition subject to differential migration inducing influences arising exclusively from said vibration pattern, so as to allow particles of said constituent material to become differentially motivated relative to the remainder of said body solely by virtue of said vibration pattern and thereby to migrate within the body of materials and to agglomerate at a characteristic destination therein, and withdrawing said agglomerated constituent material.

2. The method of claim 1, including vibrating said surface with a standing Wave pattern having velocity antinodes at two opposite limits of said surface, and at least one velocity node intervening therebetwecn.

3. The method of claim 1, wherein the differentiated constituent of the body of material is Withdrawn and collected by sweeping a current of air over said body of material.

References Cited in the file of this patent UNITED STATES PATENTS 1,983,968 Clark Dec. 11, 1934 2,071,260 Holden Feb. 16, 1937 2,591,260 Maier Apr. 1, 1952 2,755,927 Brooks July 24, 1956 2,766,881 Westervelt Oct. 16, 1956 FOREIGN PATENTS 508,675 Great Britain June 26, 1939 718,588 Great Britain Nov. 17, 1954 

1. THE METHOD OF SEPARATING A DESIRED CONSTITUENT SOLID GRANULAR MATERIAL FROM A MIXTURE OF SOLID GRANULAR MATERIALS OF DIFFERING DENSITY AND/OR PARTICLE SIZE IN A DRY STATE, THAT COMPRISES: PLACING A FLUENT BODY OF DRY PARTICLES OF SAID MIXTURE OF MATERIALS IN CONTIGUOUS CONTACT WITH EACH OTHER AND IN DIRECT VIBRATION TRANSMISSION CONTACT WITH A VIBRATING WAVE RADIATING SURFACE VIBRATED BY A SOUND WAVE GENERATOR, VIBRATING SAID SURFACE WITH A VIBRATION PATTERN HAVING A COMPONENT OF VIBRATION NORMAL TO THE AREA OF CONTACT BETWEEN SAID SURFACE AND SAID BODY, ESTABLISHING THE OUTPUT POWER OF SAID SOUND WAVE GENERATOR SO AS TO MAINTAIN THE ACCELERATION FACTOR OF SAID VIBRATION OF SAID SURFACE IN THE RANGE WHEREIN PARTICLES OF SAID BODY CAN BE OBSERVED DYNAMICALLY SUSTAINED IN A FLOWING CONDITION LIKE A LIQUID, MAINTAINING SAID BODY OF MATERIALS IN SAID DYNAMICALLY SUSTAINED CONDITION SUBJECT TO DIFFERENTIAL MIGRATION INDUCING INFLUENCES ARISING EXCLUSIVELY FROM SAID VIBRATION PATTERN, SO AS TO ALLOW PARTICLES OF SAID CONSTITUENT MATERIAL TO BECOME DIFFERENTIALLY MOTIVATED RELATIVE TO THE REMAINDER OF SAID BODY SOLELY BY VIRTUE OF SAID VIBRATION PATTERN AND THEREBY TO MIGRATE WITHIN THE BODY OF MATERIALS AND TO AGGLOMERATE AT A CHARACTERISTIC DESTINATION THEREIN, AND WITHDRAWING SAID AGGLOMERATED CONSTITUENT MATERIAL. 